Project Learning Tree is an amazing resource for educators that offers a wide variety of curriculum resources. One that I found recently is a free activity sheet from their Carbon and Climate publication for grades 6-8. By following the link you can get the activity sheet to use for free, and the whole unit is offered as an e-unit for $40. I look forward to using this with my current curriculum on carbon. How about you? How do you talk about Carbon in your classroom? Is it different in Middle school than in High school? Share your thoughts and experience!